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How To Connect Solar Battery Banks - Going Off The Grid

My wife and I have just moved to a new home and are taking it off the grid. We moved from an off grid tiny house in the woods to a not so tiny house which is currently on the grid. We hope to be energy independent again very soon.

The first thing I did was to get a shed for my solar battery bank. The batteries need to be sheltered from the elements and kept cool in summer and warm in winter.

The next step is to connect the batteries together to form a larger battery bank. By connecting many batteries together you can expand the amount of usable energy available to your off grid home.

I am using 6 volt golf cart batteries but most lead acid batteries are 12 volts. If you are using 6 volt batteries then you will need to connect them in series to give you sets of 12 volt batteries. Most off grid homes go with higher voltages of 24 or 48 volts which is more efficient. But for simplicity this article will deal with 12 volt batteries only. You can expand on what you learn here today.

So the first thing is to connect my 6 volt batteries together in pairs to make 12 volts.

Now lets go a little bit into series and parallel connections.

When you connect batteries in series the voltages are added together but the current remains the same. So adding two 6 volt 100 AH (amp hour) batteries together in series gives you a single 12 volt battery at 100 AH.

When you connect betteries together in parallel the current is added together but the voltage remains the same. So connecting two 12 volt 100 AH batteries together in parallel gives you a larger 12 volt battery at 200 AH.

I am going to use a combination of the two in order to get a larger 12 volt battery bank from my 6 volt batteries.

If you are using 12 volt batteries then you can skip this step.

I connected my 6 volt batteries in pairs, in series. Connect the positive terminal of one battery to the negative terminal of the next one. Now I have a 12 volt battery. I set up 4 of these sets from my 8 golf cart batteries.

Connecting lead acid batteries in series to increase voltage

Next I connected the battery sets in parallel to increase the current capacity.

I have 4 sets of 12 volt batteries rated at 225 AH each pair. By connecting all the positive terminals together and then connecting all the negative terminals together I now have a large 12 volt battery bank rated at 900 Amp Hours.

Connect batteries in parallel. Note the red circles. Plus to plus and minus to minus.

If you are using larger voltage battery banks then simply adjust as desired.

By increasing the overall battery bank capacity I am now able to run larger loads in my new off grid home.